FIELD OF THE INVENTION
This invention relates to a vehicle surroundings monitor and, more specifically, to a vehicle surroundings monitor which monitors the surroundings of a vehicle such as an automobile to support a driver in checking safety during vehicle driving.
A vehicle surroundings monitor for automobiles has been available, in which the distance to an obstacle is detected by measuring the time it takes for an ultrasonic wave, which is emitted from an ultrasonic wave transmitter and reflected by the obstacle, to return to a wave receiver.
There is also a method in which a television camera is mounted on the rear part of the roof of a vehicle so that the driver is given a rearward view on a TV monitor of an interested area when the vehicle is moving backward.
Of the above-mentioned conventional apparatuses, the one which uses the ultrasonic wave transmitter and receiver cannot detect the positions and sizes of obstacles and ditches and the depths of the ditches. Hence, it cannot fully support the driver in confirming safety in the near surroundings of the vehicle during driving.
In the method that uses a TV monitor, on the other hand, it may be difficult to distinguish the obstacles or ditches from the level ground depending on their shapes. Especially during nighttime, there may be cases where obstacles cannot be identified unless sufficiently illuminated.